Here is a compilation of maps created for UT3 till date:-
http://forums.epicgames.com/showthread.php?t=598982
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I recommend :-
Dm Shrine
PC
http://forums.epicgames.com/showthread.php?t=593544
PS3
http://www.fileplanet.com/183258/180000/fileinfo/Unreal-Tournament-3---DM-Shrine-Map-(PS3-Only)
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DM Conveyer
http://forums.epicgames.com/showthread.php?t=593618
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DM Krodan
PC
http://download.beyondunreal.com/fil.../dm-krodan.zip
PS3
http://files.filefront.com/DM+Krodan+PS3+for+UT3+on+3zip/;9298313;/fileinfo.html
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