Hi Jesse,
Sorry to divert you over here but the subject of marriage in the Philippines can/does create a lot of posts typically and it would have buried the 13a visa subject in that thread.
Your concern in your post was that marrying a foreigner can be complicated. I'm making the assumption that you're referring to you as the foreigner getting married in the Philippines, and not complications about you marrying a foreigner from your home country perspective.
Getting married in the Philippines is not complicated. It takes a few more steps than most of us are probably used to (especially those of us from the U.S.) but it's just a step-by-step process.
Overall the costs are not very expensive but the whole process (start of paperwork to marriage) will take some time, and then getting your official Marriage Certificate will take some more time (not more work really, just more time) and you need your marriage certificate for things like your new wife's updated passport, bank accounts, etc. The waiting can be frustrating.
I'll keep this as short as I can (but no promises, I'm not good at short). I refer to NSO/PSA in this post. Most people still call it NSO (National Statics Office I believe) but the name officially changed a few years ago to PSA (Philippine Statistics Authority, if I have that right).
To get married (and I'll further make an assumption your girlfriend is over 25) in the Philippines the first requirement is that she have a CENOMAR (basically a document from NSO/PSA stating she is not married) and you have a document called a Certificate of Legal Capacity to Contract Marriage. Depending on your home country, how you get that will vary. If you're from the US, you can't get one, but the Embassy in Manila (and you have to go to the embassy for this) will issue an Affidavit in Lieu of Legal Capacity to Contract Marriage. This is accepted by almost all civil registrars in the Philippines, but not all, so check with your local registrar (the one nearest to where your girlfriend lives would typically be the one). If they won't accept it (very unusual) you'll need to find another that will.
So, that's step 1: CENOMAR for her and Certificate of Legal Capacity for you.
And while she's at NSO/PSA getting her CENOMAR she should also get copies of her NSO/PSA birth certificate (at least a couple but I'd recommend 3 or 4 since everyone seems to want them, they're not that expensive and usually getting documents from NSO is a pain-in-the-tail (literally, since you sit waiting forever)).
If you've been married previously you'll need certified copies of your divorce papers. You may need them for your Legal Capacity to Marry certificate but you'll definitely need them for the marriage license. Probably.
I say probably because it seems every registrar, city office, province, etc has their own way of doing things. I read up on the marriage process many times before I got to the Philippines and then when we went through it, it was nothing like what I had read about, so there seems to be a great difference between someplace like (say) Manila, and in the provinces where one person in one office handles everything. Be prepared for things to go however they go.
Step 2 for her is getting her required clearances from the police, and/or barangay, and the local tax office. Even though my wife had never been married before (and was 42 at the time) she still knew how to do all this stuff, apparently it's a rather routine thing for many situations. Your girlfriend shouldn't have any trouble with this.
Personally, the first thing I'd do (looking back on the process) is go to the local registrar, tell him/her you two want to get married and ask them for a list of the requirements. If you cross those T's and dot those I's you're home free. If you do what they want (as opposed to what you find online) they'll be happy and your life will be good.
Once your girlfriend has the paperwork she needs in hand and you have your certificate (of Legal Capacity), and divorce papers if you need them, it's really just a matter of filling out the marriage license form, then waiting for the time to go by while it makes its official rounds and the required time goes by (this took about 10 days for us but that can vary a lot!).
Then you get married (the easiest part by far for me).
After that they finish up the paperwork and then it somehow gets sent to NSO/PSA. I say somehow because this is where there was another bit deviation in how it was "supposed" to work according to what I found online. In my case they told me how much the cost to send it by courier was, collected that amount from me, and that was that -- no options. Your mileage may (and probably will be) different.
I was able to get copies from our registrar's office while waiting for our official NSO/PSA copies. They weren't certified precisely but at least stamped and signed, so we could "prove" somewhat that we were married. That said, my wife could not change her SSS ID card nor her passport until we had the official marriage certificate from NSO/PSA. From the time you get married until you can get the official NSA/PSA copies of your marriage certificate is typically 4 to 8 weeks. I have heard of it happening faster (and also later) but there doesn't seem to be anything one can do to alter the situation, it just takes the time it takes.
By the way, the mayor of our town was out of town when we got married, not a big deal (I thought) since he wasn't the official that was marrying us. However, after we got married our papers sat on his desk for over a week before they got send off to NSO/PSA. It wasn't until I complained a bit that they found the papers on his desk and then had him sign them right away.
One more thing that's often overlooked -- Your (now, at this point) wife married a foreigner, in order to update her passport (especially if she took your surname) or leave the Philippines she must take the CFO course in Manila or Cebu. I knew about this requirement if I wanted to take my wife to the U.S. but I did not know that it was required even if she wasn't leaving the Philippines in order for her to get a new passport (or renew her old one if it expired).
The CFO thing is convoluted and you'll hear a dozen different situation where it is, or isn't required. The bottom line, in reality, is that once you're married she needs to take the course (I think it's like 4 hours) or it will plague her (and you), without it her passport is only as good as the length of time remaining in it, and then only if she didn't change her surname.
It's typically a 2-step process: she takes the course and gets a certificate, that's step 1. Step 2 is when she's ready to fly somewhere she goes back to the CFO office to get the CFO sticker affixed in her passport (this is a quick process that requires no additional money or even an appointment). However, when my wife and I went to the CFO office in Manila the day before we were flying to Malaysia we were informed that she didn't need the sticker in her passport (and in fact, they wouldn't give it to her) because she wasn't flying to a country that required a visa. Subsequent research on my part did turn up this information as correct and we didn't have any trouble with her check out at the airport the next day.
What no one could tell me is what happens if we leave (now) Thailand (or really, anywhere but the Philippines) directly for the US? I'm not worried about US immigration, they couldn't care less about the CFO sticker but it might be interesting if we arrive from the US back to the Philippines. Oh well, another bridge we get to cross when we get there. It's always an adventure!
Hope there's some useful information here...
Les
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