http://hiddenwiki.i2p/wiki/index.php?title=Network_Attributes_of_your_computer&action=edit
Once you have it installed, you can go to [http://localhost:7657/index.jsp the config page] and check to see if it is able to connect.I2P opens a proxy server on localhost:4444, but most likely you will want to add a line to your privoxy config so you can use both I2P and tor.