hey ya'll I want some puzzle games on here that aren't adventure games, but casual games.
only problem is, the few that I know of either aren't on PC, are cloned too frequently to keep track of on PC, or are too new for the site. so if you would please list some amazing PC puzzle games and also, put them on the wishlist so we can vote for 'em. I'm tired of all these serious hard core games (other than the two pinball games.. pinball is fun but it isn't really a puzzle game..)

Puzzle Quest? Naw, it's more of a RPG thing as well. Most puzzle games I play are from PopCap and they have their own store, so I wouldn't really expect to see them on GOG.

One I remember from ages back is The Incredible Machine by Sierra. It had a series of challenges to go through by arranging devices to move the object(s) to the target (some of which were frustratingly difficult to solve), but it also had a freeform mode where you could build your own amazing invention with all the available components and then set it in motion. You could also save your creations for later. It was very successful and saw a number of sequels.
Another fun oldie is Lose Your Marbles by SegaSoft. It's a matching game where you make groups of identical items, but unlike others in the genre you have to move whole columns rather than being able to swap pairs, and you have to balance building up big groups for more points against the prospect of new marbles entering the field at regular interviews (the columns have to always have one marble on the centre line, and if the board fills up you lose).

The 7th Guest is fun also but is an adventure I guess. It's not like Myst, Dragon Lore or the Zork games but isn't as casual as Peggle.
You could also try the games on the Kongragate (sp) site.
Karl

Oh man pushover. I used to play that alot on my SNES back in the day.

Yeah, JoWooD have some okay puzzlers. Strangely enough they've released most of them on GamersGate (for €5), but not on GoG. Maybe they'll be released here in the future.
But in general, old puzzlers weren't very "casual". They were usually quite hard. I saw you (Weclock) said you found World of Goo too hard in another thread - well, most older puzzle games are much harder than that. So while I would expect some puzzlers on GoG eventually, I don't think there will be many casual games among them.
So your best bet is to go to BigFishGames, ReflexiveArcade, PopCap, PlayFirst, et.c. or XBLA/WiiWare/PSN. There's plenty to choose from there.
Edit: I remembered that GoG have a deal with DotEmu (Robinson's Requiem). So we'll possibly see some puzzlers from Silmarils here, like Boston Bomb Club. That was pretty decent on the Amiga at least. Here's a list: [url=]http://www.dotemu.com/index.php?page=catalogue[/url]

Was The Incredible Machine a puzzle game or just a construction kit?

Both.

There was sandbox mode and puzzle mode where you received a preset amount of stuff.

Lemmings surely counts as a puzzle game too

certainly, this is some great stuff.
edit:
also, somethings I take issue with and somethings I don't surely world of goo isn't too hard for me, but simply that I don't feel that it's worth the amount of time necessary for me to continue playing the game. a game like Puzzle League.. sorry, maybe I should have specified I want games along the lines of Tetris, Puzzle League, Puyo Pop, Yoshi's Cookie.. those kinds.

A great timewaster for me is Fill it
which is basically about drawing lines to reduce the space available for the little flying things which... Hmm... I'm not doing a great job explaining, but its fun and quick. Once you get up to level 10 it's a bitch though, ten little flying dudes getting in the way, not sure how far you can get - 10 is my limit, and usually I've lost my three lives well before that.

Crazy Machines Series are also good.

In other words, it's a clone of the same gameplay as , [url=http://www.mobygames.com/game/dos/volfied]Volfied and others of the kind.