Welcome to CF! I'm still a newbie here myself...and a newbie sailor having a great time. We bought our first sailboat to learn on from a listing on craigslist/ebay (seller had several listings) and we couldn't be happier. We picked something that met our needs in both price
and amenities. We didn't want something too big to handle for our first boat so we went with 25ft. although, now that we've sailed her a bunch of times...I'm sure 30ft wouldn't have been too much. Good luck with your boat hunting!