Ben,
I'm including a few links. These are certainly not necessarily the best, and may not be the cheapest, but are intended to provide you with some information on what sorts of things to look for.
MSA cartridges for painting (organic vapor + N95 particulate): http://www.discountsafetygear.com/ovrecaformsa.html
Here's the MSA respirator with cartridges included: (This is what I have; it's excellent!)http://www.discountsafetygear.com/msaadvov.html
Here's a 3M half-mask respirator (5000 series) with OV + particulate filter: http://www.discountsafetygear.com/3m50sehamaov.html
Here's a North half-mask: http://www.discountsafetygear.com/nosihama.html I wear this at work occasionally. Quite comfortable.
North cartridges: http://www.discountsafetygear.com/refiforno77s.html The combination cartridges shown are overkill, but will still do the job. If you buy from a safety place such as this, ask if they carry cartridges suitable for painting.
(A look at the North catalog: http://www.linkpath.com/data/issuePDF/N1/1500000261-N1.pdf shows on page 16, Cat #7581P100 a combination OV and P100 particulate filter, and on page 17, Cat #7531N95 shows a particulate filter assembly that snaps over a plain OV cartridge(Cat #N75001). Both are suitable for painting.)
A couple things to keep in mind:
1. Respirators are sold in S, M, and L sizes. Typically, if you're "average" size, and have a fairly narrow nose and "average" face, then a medium will usually fit in most circumstances. If, however, you're heavy set, and/or have a wide nose and face, a large may fit you better. If you are black and have the genetic wide nose and attendant facial structure, I have found that this respirator seems to work quite well in both the M and L sizes: http://www.msanorthamerica.com/catalog/product583.html Of course, there are always exceptions in every case. If you have the chance, visit a local safety supply house and ask if you can try on a couple manufacturers and in various sizes.
2. You cannot interchange cartridges between manufacturers. An MSA respirator cannot be used with 3M or North cartridges or vice versa. In addition, you can't put MSA Comfo Elite cartridges on an MSA Advantage 200 respirator. Cartridges are usually sold in pairs, or in boxes with even numbers. When cartridges go bad, they go bad together. Change them both at the same time.
3. If you have questions about a specific brand and what is offered, ask someone. Buying from a safety supply house is often advantageous, because they have folks knowledgeable about the products they sell. If you want a respirator and cartridges for painting, they usually won't try to sell you one for asbestos abatement; the liability is too great.
4. Care and feeding: I found the post! /forums/142964/ShowPost.aspx Lots of good info there.
There's about a book's worth of info I could write (and I'd have a cure for insomnia!), but I don't wanna. If you have any more questions, please don't hesitate to post 'em here!
Hope this helps.
Gip Winecoff