You can join an affiliation scheme as a merchant to help market your products through other sites (known as Affiliates) who are looking for ways to earn revenue from their own. If they like what you do they place your banner link on their site for which you pay a commission to them for every sale you make that came through from their site.
It may be a bit too expensive for you just yet so I would be inclined to stick with linking for now & consider selling on ebay too if you don't already. Much cheaper than the affiliation schemes but take a look at www.affiliatefuture .co.uk
anyway. Their site's easier to understand than some of the other ones!