I am a single gay dad with three fabulous kids.
It is FIRST crucial that you research the laws in your state--many states leave you vulnerable to losing your child. I chose California, since the surrogacy statutes there have been tested and codified. The travel expenses and birth hassles will be well worth your peace of mind later--I was even able to remove the surro-mom's name from the birth certificate, something I couldn't do I my home state. My surro moms happily expressed milk for the first month so that when we returned home after 30 days, our babies had a healthy start.
SECOND: I had no contacts and felt uncomfortable with internet connections, so I contacted a surrogacy agency. There are agencies who are gay friendly, and even agencies that specialize in glbt. Caveat: Expect to pay a total of $50K to $150K, I kid you not. If you are lucky, you will succeed on the first try and save some bucks. I got one for 100K and twins for only 60K--go figger. I know that you could also save some by networking with a local community center or just putting the word out and bypassing the agency but you must still retain an attorney that specializes in surrogacies.
THIRD: Go for it! I'm blissed. ↑