The best distributor I have found for such products is DandH.com. They have thousands of products. I've used them on a few things. They have a dropshipping system but I've never used it. They are willing to work with quantity discounts. They also offer free shipping on orders over 1000 USD. They are a huge distributor so their products fluxuate for quantity on hand on most newer items.
All that to say they do have Adobe software. If you are a regestered educational reseller then you get even better deals. Unfortunately, Adobe software is extremely expensive even at the wholesale costs.
If you are looking at selling software, you should look into Microsoft products. Regester at microsoft.com as their resale partner program and they will give you links to all of their major distributors (one of which is dandh.com). Microsoft products will often offer better quantity discounts because their products are used in so many different platforms: servers, pc's, laptops, macs, etc.
Hope this was helpful. Good luck.