Here are some vendors I have had personal experience with. They are not giving me a kickback or any "promotional consideration". I will post links to those with whom I have had a positive experience. I will not put links to those I have not had a good experience with. (As my mother used to tell me, do not say anything if you do not have something good to say.)
Tower Hobbies - The Wal-Mart of R/C. They are late comers to the world of Electric R/C, but they are catching up. Their service is good, shipments are carefully packed, and problems are quickly corrected.
Horizon Hobby - They carry Hangar 9, Spektrum and E-fllite to name a few brands. The service is reliable and quick.
Todd's Models - a small mail order business offering quick and personal service. And, his prices are most reasonable.
LightFlight RC - A newer, small company which supplies Thunder Power batteries at very reasonable process. The service is fast and personal. I am getting most all my batteries from them
Bob Holman Plans - I have built two models from laser cut parts and plans I obtained here. The service is first rate, and the quality of the merchandise is excellent. If you like building and/or old time and vintage models, you have to browse this website. Having many of the parts laser cut takes a chore out of scratch building.