I have a Canon T3i and Premiere CS5.5. When I create a new file, it shows me an option to choose what type of footage I will be using. Obviously I choose the T3i 1080p 24fps version (I prefer 24fps). Importing my T3i footage is prefect! no problems at all! The problem comes when I try importing .wmv, .avi, and other video formats. What happens is it will show a black screen for the footage, and only play the audio. I don't know what to do about this, and it would be great if you could help with this. Thank you guys in advance.
My guess is that the other material uses delivery codecs, like DivX, Xvid and the like. Delivery codecs are not suitable for editing, so you need to convert the material externally before bringing it into PR. Use Google to search for conversion programs.
CAVEAT: Do NOT install codec packs like K-Lite to solve this, because all they do is making your system highly unstable, often requiring a fresh install of Windows and programs.
I'd agree with Harm. Premiere Pro is a professional level program, designed to work with standardized media from cameras. Using ".wmv, .avi, and other video formats", you take a chance that it may or may not work.
If you stick to using media you shot yourself using a supported camera, you should fare better.