A new mouse would be good and you may want to try mousing with your other hand. It takes about 3 days to become functional at this and about 3 weeks to become proficient.
Continue with the ice, arnica etc. Good call on the massage therapy. Posture is very important for these things. Usually, it's not just an elbow issue, it's often a stiff neck/pinched nerve/problem shoulder that is leading to a complaining elbow. We call this the silent villian and screaming victim scenario. Think about your whole upper body kinetic chain, sit up straight, reach away from your body as little as possible.
I also rec. tennis elbow braces, I prefer the ones with a gel pad that goes over the tendon area.
Here are some stretches, do them gently:
http://www.acefitness.org/getfit/exe...spx?pageID=366
I recommend holding for 20 seconds and repeating each 4 times twice per day. It's usually not recommended to stretch after icing (tho that's a bit controversial).
Hope that helps.
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2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
2014 Soma B-Side SS