Are Mod-chips only available via mail order?

[Porkchops]

One other question to you all (if you can't tell I'm new at this whole business) - all I really want to do is backup my Xbox games. I lost Halo when my nephew stepped on it, and would really like to not have to rebuy games again I have evolutionx works with any mod chip out there... so my question is, with that being my criteria (I just want to back up stuff and still be able to play on Xbox Live), what chip would y'all recommend?