so, I have came about to the decision that I would like to buy Season 3 of Sam and Max, but I have one question, is any or much information about the Comics, TV show or the the past two season's needed to enjoy this season. 
If you choose to answer then I thank you.

I haven't played it yet, but I think that they made it so they could gather new fans to the series, so you shouldn't worry. The two other seasons are still great, so you shouldn't skip them, and they can be bought fairly cheap now.

Yeah I think they're using this season to gain new players, so be one of them! 
 
Personally I'm still working on season one, and have been for like... years now. I'm kinda stuck on whether I should finish it and 2 up before three, or just do them later. 

I would like to buy every season, but money is an issue so I would like to get season 3(As it seems to be the most accessible) and then work my way back through seasons 1 and 2 if I like it enough.

The other seasons are great, but, no, you do not need to play them to understand Season Three.

There are jokes I recognize as being references to Sam & Max Hit the Road and such, but it's all good: You don't need to know about sizzling Weasel on a Stick™, Trixie the Giraffe-necked Girl,  or anything like that. Though you really should ;-)