Here are a bunch of sites which I hope my year 12 class will find useful as we read some of Horace's Odes.
You can of course find the Horace’s complete works at the Latin Library .Translations of all of Horace’s poems can be found at Perseus (with notes) or at about.com. Unfortunately some of their translations can be a bit hard to follow. These three sites (with notes) have better translations but only offer a selection of poems.
Wikipedia of course has information about Horace's life as well as a separate page on the Odes. Here you will find some other useful links for both Horace and Catullus, and this site has some hard core information on Horatian meters in case anyone is interested.