Jeff, this may not be the best place to get safe sex practices advice. But can relate, I had some questions myself when I first started. The internet has lots of info, you could probably google your exact question, and get some hits.

Ever given a blow job to a girl wearing a condom? Some girls insist on them, others not, but if you want to play safe, I guess that is your option.

Unless you have some really great skills in in the bj department, don't think you have to worry too much about ladies coming in your mouth so much to start. Stomach acid? hah, that helps, but you should also look up peanut butter as a solution, as it can also aid in this particular situation.

Good luck.