f you want, you can actually extract the background image from a uisearch bar and make it a stretchable image to use as the background of a UITextField. I did the same thing and it works like a charm for me. Here's the code i used to extract it:

UIImage *img = [[[self.searchBar subviews] objectAtIndex:1] background];
NSData *imgdata = UIImagePNGRepresentation(img);
NSArray *searchPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
NSString *documentsDirectoryPath = [searchPaths objectAtIndex: 0];
[imgdata writeToFile:[documentsDirectoryPath stringByAppendingPathComponent:@"searchbarbg.png"] atomically:YES];

Nice!