as a strict IDM head, i definately agree with others on the following alums:
[i re-read my post and i have to give my opinion on IDM as a genre. the reason i love IDM so much is because it's so unclassifable. when you can't take an electronic song and stuff it into a genre, you call it IDM.

how cool is that? it's
always different! ok back to my post.]
i concur on the following albums:
aphex twin - i care because you do
speedy j - a shocking hobby
if you like heavy stuff (i'm assuming you like metal), "a shocking hobby" will entertain you perfectly. it's dark, agressive, dirty and a real work of art.
"i care because you do" is my favorite aphex twin album of all time. it's just so interesting to listen to all of the organic pings, clinks and clangs and it doesn't challenge me too much....which is good for times when i need a bit of nostolgia and relaxation. these are amazing albums to be introduced into IDM with.
i hope you aren't scurred away because i always get excited when non-electonic music listeners open their minds to experience the wonders of the dynamics of electronic music!
i love all kinds of music, but there's more to sounds than guitar, bass and drums!!!!!!! (rock)
thanks for the interest and open-mindness!