Where to get good weapons in oblivion for the ps3?

once you are lvl 20 search the oblivion gates. you will find everything from elven and glass to ebony and daedric.

Travel around The Imperial city and sooner or later you will come across some weird looking ruins. Inside, you will find a wood elf wielding a sword named Umbra. Kill her and take it. Note; you cannot drop Umbra once you have it until you complete the daedra missions, which u need to be level 20 to do, so i'd do that first unless you're planning on using it the whole game.