Blurry viewfinder While the viewfinder has always been a little blurry, I've had a recent problem with it being so blurry you couldn't even use it take a picture. Then after swtiching to the LCD viewfinder to shoot from, I see a large yellowish black line on the left side of it, doesn't seem to affect the pictures as I can view them afterwards ....am I going to have a major repair>

As mentioned, might be a defective CCD imager. You may be in luck. Canon should fix this for you for free, including free shipping both ways. Please check the following two links for more info:
http://camerarepair.blogspot.com/2007/11/canon-digital-cameras-showing-black.html
http://www.usa.canon.com/consumer/controller?act=PgComSmModDisplayAct&fcategoryid=225&modelid=13390&keycode=2112&id=29819
Applicable cameras include:
A40, A60, A70, A75, A80, A85, A95, A300, A310, S1 IS, S60, S200, S230, S330, S400, S410, S500, SD100, SD110

Your Canon camera falls in one of the models that had a bad CCD imaging sensor. I do not exactly know how your screen looks like, but try to visit the follow link to read the article that is related to these camera problem, or go to your country's Canon site to find the 'Service Advisories' to learn about Canon's updated comments on their products, new or old. The link that I mentioned above: http://www.imaging-resource.com/badccds.html If you have difficulties finding the related service advisories from the Canon site. Simply find their contact tel. no. and give them a call to find out how they will handle the situation. It's worth the time to do so, as it will be free of charge to get your camera fixed, including both way shipping costs if shippings are required. The link above will bring you to a web page containing sample images of the screens being affected by the bad CCD. Make sure they match the problem of yours before proceeding to the next step. Good luck. Paul