It's easy - just select the desired access level, copy this link and send it via email, instant message, etc.Link: Just a link to your wiki. Post this anywhere and people can ask you for the invite key.
Online Dictionary. Here is a good Japanese/English dictionary.
Browser plugin dictionary. rikaichan is a is a very good plug-in for firefox that translates pages from Japanese to English.
You can also add a google translate search to your firefox search bar. Just cut and paste the URL and let google work its wonder. Definitely not perfect translations but quite helpful.
Rikaixul is also a plugin for firefox but it does not seem to work in Firefox 1.5.
Learning Kanji
Learning Kanji can be very difficult. One method developed at Nanzan University by James Heisig uses a different method. Some people find it very helpful, others hate it. You can try it out for free with this pdf download of the first 126 pages.