[LAU] mastering - do I need it?

Hi I almost finished a cd of electronic music with my linux laptop. Now I'm thinking about making an actual cd of it. Now I'm wondering if I need to pay for mastering... I think the recording sounds quite good by itself, but I have a vague idea of mastering doing something magical to my audio. Can anything general be said about the need for mastering of electronic music? Also, can I do a good enough job with jamin? Are there any tutorials that I should read? What will I be aiming for in the process, considering I think it sounds fine already? Any input appreciated! -- peace, love & harmony Atte http://atte.dk | http://myspace.com/attejensen http://anagrammer.dk | http://modlys.dk