My main influences as a cartoonist are Chester Brown, Seth, Pont, Chris Ware, Hergé and Milt Gross, but you'll have a hard time finding any resemblances to their work in my Panopticum stuff (I'm very much focussed on technique, rather than style, if you know what I mean). I'm pretty confident that my bean people are my own thing.
The best one in that list is no doubt Chris Ware, who masters pretty much everything comics related, so if you don't know him, check him out, 'cause he's totally worth it.
The best artist out there is still reality. I'm much more influenced by isometric games, for instance, than by other cartoonists (which is a good thing). If you want to draw cities and buildings, then a book on architecture is way better than imitating your favourite cartoonist.
For my iso drawings, for instance, I'll sometimes buy a 1:72 plastic model kit (of a plane or a car or whatever), so that I can look at the "real" thing and translate it to my own style. Or I'll make a model myself (I frequently make critters out of FIMO) so that I can very easily place them in certain environments, change lighting, POV - and all of that in real time.
I also looked into right/left brain drawing techniques and that really paid off.
In short: everything I see, hear, read, feel... has the potential to influence me more than my favourite cartoonists do. And I think that's the best way to do it (but probably not the only way).