For a price, that is. http://sokuyomi.jp
A relatively cheap one, though. Some stuff goes as low as 294 yen. If you look around more you can probably find lower prices too. This site is limited to Shogakukan, though. I've found it's been useful for when I can't find raw scans of older series (...and don't want to buy the actual volume because of the high shipping).

Anyone know if there other publishers with sites like this? I've been trying to find one for Tosuisha in particular.

Anyway, before you buy anything, make sure the manga viewer is compatible with your browser (by clicking the試し読み button first). The site itself states Mac users can't use the viewer with Firefox or Mac version of IE. I tried it with Camino on Mac OS and it works fine.　

I'd rather do a quick google search for lurk manga and download the cbrs of whatever raws are available (tons).

Sites like these are a good last resort for when you can't find raw scans~ It'd be cool to find others aside from Shogakukan releases though.