Sphere of Hip Hop is one of the very best resources online for Christian Hip Hop. One of their great features is their daily download. The download can be gotten manually [by clicking here] or if you are an itunes user (and let's face it, most people are) you can schedule it to download as a podcast each day [by clicking here]. To catch up with all previous downloads there is a long list of tracks to choose from. [available by clicking here]
I think one thing that is important to mention is that as a listener you should always test what you are hearing with the Bible. Some of what pupports to be Christian/Holy/Gospel Hip Hop can be as damaging as listening to Hip Hop that only pushes sex, violence and all round immorality. If you hear something you're not sure about - look to the Bible, or someone who knows the Bible well and find out whether what the MC is saying squares with the Scriptures.
Some tracks will teach you new and exciting things about God, Jesus, The Holy Spirit and Christian life - so long as the artists are engaging in study of the Scriptures. Sometimes things may sound radical - but the Bible brings a radical message so don't be too quick to slam an idea - look into it. Use your musical preferences to initiate your own study and meditation.