For generic throwers, there really is no good way. Online market (ebay, facebook, DGCR, etc...) does not pay a whole lot for the discs. If you goal is to move a good chunk of them you will have to price them low, plus lose about $3 per disc in shipping. Personally, I use DGCR, but I price them at what I am willing to sell, not necessarily the market price. As a result, when I list 100+ discs, I generally only sell a dozen or so. By using the DGCR disc organizer, it is easy to keep track of the ones I have, list them, and keep pictures.
I don't do lots, but from what I have seen, the smaller / more specialized (all the same discs) the more you typically get per disc. If it is a bunch of random discs, you won't get much per disc.
1 disc: As DiscJunkie said, bubble mailer USPS first class (mine this morning was $2.45 postage). I buy the bubble mailers from Sam's in bulk. They sell 25 for less than $10.
2 discs: USPS flat rate envelope
3 discs: Tough call. May depend on the zip code you are sending to. Package rate may be cheaper.
4+ discs: USPS flat rate box
Last edited by JRW III; 04-23-2014 at 10:49 AM.