Hello everyone! I recently purchased a Canon T3i. When I purchased it I also got a small back pack and a 75x300 lens (I apparently made the mistake of getting one that doesn't have auto-stabilization, so I don't know what situations I can actually use it in). What are the basic accessories and lenses you recommend for someone just starting out? Also, did I totally screw the pooch with the telephoto lens? If not, what are the best situations to use it in?