Uhh... Sign up for an affiliate program and post some convincing text along with the link as a status update? :\
u cant post affiliate link now on status , or in msg , facebook has filtered it , only way is to buy domains , make them redirect to the affiliate link
I think facebook dont allow any anonymous link sharing. The best way is to make a fan page or a group and write some attractive description of ur product. In the end write " for more details contact me" or something like that. I use my the link ezmoneyjobs.blogspot, I hope writing this link in DP is an issue. All the best!