I use Nasonex, Zyertec and Astelin and some days it still isn't enough. The astelin tends to do a pretty decent job of letting me breathe through my nose though, even if it doesn't always last the full 12 hours. In terms of over the counter stuff, I have this spray bottle the allergist gave me that you fill with a saline solution in distilled water and basically go and spray it up one side of your nose and then work it so it comes out the other side. It is supposed to help get rid of all the garbage up in there. This is the first time in more year than I can count that I didn't end up with a sinus infection or 3 in the last year, so maybe it really works... If you are interested I can look at home and see what the official name for it is, cause I don't think it is "nose spray bottle"
I have also found that at times when my allergies get bad from dusts it can dry out my nose and make me sneeze a lot, and then I use Ocean nose spray. Again it is an over the counter saline solution, but works really good on "wetting" everything up there and cleaning out some of the congestion so that I am not so sensitive to everything in the air.