Motorola MPx220

I have owned my MPx220 for years and it is the best phone I have had and it still is better than 99% of the phones available today except for one problem that I hope someone can help me solve. My phone was purchase as an Unlocked phone from Germany (I think) and shipped to the USA. I can get on the Internet as retrieve some very limited information but 90% of the sites I try to see are unavailable to the phone. The phone is on AT&T's network. Does anyone have any suggestions that would broaden my Internet capabilities on this phone?