TR custom parts sells a great pre-fabbed kit that has been installed on TONS of cars, called the Tin Man Big Mouth Cold Air Kit.
If you are looking to build your own kit and make your own plumbing/inlet for the MAF pipe, take a look at www.siliconeintakes.com for pre-bent aluminum piping in multiple different radius bends in different sizes and it also has bead-rolled ends of the pipe as well. The silicone hoses come in a ton of different radius bends and sizes, and even has reducer bends (for example a 3.5" inlet on one side of the hose, and the other end of the hose is 3", and they have this style for both straight hoses and bends) in case you need to change hose size at the bend. They also offer stainless t-bolt clamps and thick vacuum line.
The Tin Man Kit is a proven, tried-and-true kit that has great fit and finish to it. The only time I would suggest to make your own maf piping setup is if you have a custom mounted turbo or intercooler that would locate your turbo inlet for the maf pipe in a position that is not stock, and thus the regular cold air kits would not fit.