3 Hives is a great place to start. I always recommend that people start with a minimum of 2 hives and 3 is better. Gives you a basis of comparison to have.
There are a few beekeeping supply outfits out there. The one I use the most is Mann Lake (mannlakeltd.com) or then Dadant (www.dadant,com
). They both sell everything you might need to get started.
Stings are a part of it. If you suffer from arthritis though the stings will help to alleviate the pain from it if not eliminate the pain altogether. Over time I have become desensitized to the stings (no longer swell up from them or get itchiness) and rather welcome them to address the arthritic pain.
Read the books. You have plenty of time since it is way, way too late to get started this year. You need to put the stuff together and educate yourself for next spring.