In terms of self distributing dvds and ebooks it seems nothing really competes with the megalith Amazon. They have two main systems (bookbaby & createspace) that give lots back to producers vs. conventional distribution company platforms.
DVDs: Amazon/CreateSpace deducts a $4.95 fulfillment price and a 15% royalty. Hence a film selling for $15.00 would earn a net profit of $7.80 back to Windpath Films and Amazon would handle all packaging, universal bar coding, DVD pressing, basic visibility/marketing, and in depth sales tracking.
There may be a huge downside in terms of marketing, but if you can swing word of mouth and have a solid product tied to festivals and online social buzz this is probably a good way to go.
But the best resource of today relates to Interactive Media knowledge gathering. The Bell New Media Fund here in Canada is a great resource! And their Bliki is second to none!
http://bellfund.ca/bellfundbliki/
peace,d