I was wondering if anyone has had success with any particular connector/mount scenario that works well for plugging in a balanced XLR mike to the T2i's mini-plug jack.

I have played around with it a little; but don't have a good audio store locally to go in and experiment.

Looking for some advise!

buy a separate recorder, best advice I can give.

Depending on what mic you have it can be just a matter of a cable that you can purchase pre-made
if your mic requires phantom power then its a whole different topic and you will need either a preamp or recorder that can supply this.

This topic is extremely well covered if you do a search.

I for one believe the audio circuit in a T21 isn't worth the effort in trying to make work for anything besides ENG type stuff and then only if you use Magic Lantern and other stuff. which is a operating system hack that could potentially turn your camera into a paperweight.

I would recommend you getting a recorder that can deal with a good mic and syncing in post.

GG

What I'm moving towards for run and gun is mounting my h1 recorder and a shotgun mic or wireless receiver on the camera. I can use the h1 as a preamp with level adjustments and level meters, sending the audio out to the camera. And even record in the h1 simultaneously for backup and higher quality if needed.

For situations where more equipment won't weigh me down, using a SD mixpre gives easier level adjustment (dial) and a more readable display (colored LED) as well as probably slightly better noise floor and clipping behavior, not to mention phantom power and a 1k calibration tone for aligning pre to camera.

Thanks for the advise guys!