So I just downloaded the 'The Bends' album by Radiohead, as suggested in another thread.

My question is, based on the style of music on that album and NOT the trippy / agonising stuff they did later, what bands are similar to Radiohead?

Radiohead are Uniquely awesome and you're gonna struggle to find a Album as great as The Bends. A lot of people compare Muse to Radiohead. They've got a very similarities but for me Muse just aren't in the same league. Some Porcupine Tree also sounds similar to Radiohead. Try Lightbulb Sun as a starting album there.

You could try Pineapple Thief.

Try Faunts:

http://searchbeta.playlist.com/tracks#will%20you%20tell%20me%20then

I sent this song to a friend of mine and the first thing he said was "They sound like Radiohead". I can see where he's coming from, but I think they have a different vibe.

However, I don't know what you mean by "trippy/agonizing stuff". You might think this is "trippy" too, I don't know. I just think it's good music.

I second Porcupine Tree.

I'd recommend their album Stupid Dream. The Bends is even referenced in the song "Pure Narcotic".

Or on a simlilar note, go for something different?

However, I don't know what you mean by "trippy/agonizing stuff". You might think this is "trippy" too, I don't know. I just think it's good music.

I mean how later Radiohead the singers voice sounded like he was in agony, I guess it finds the mood of the music and that but I don't find it appealing.

That song you suggested is pretty good though :)
And, I'm downloading those two Porcupine Tree albums now, cheers.