Make sure it is an EF model T5 or your shifter position may not match up with the hole in the trans tunnel.
Otherwise what they all said above is 100% correct..
Everything you need is easily available via weckers, and is easy to fit
Wrecker may be able to sell a conversion kit. Manual ecu and even engine loom is handy, but means no more speed sensitive power steering if you have it as the manual loom does not have the supporting plug.
From what others have said i understand you can trick the auto computer to drive a manual, but for me i would rather have the real deal.
Let me know if you decide to go ahead, only to happy to assist.
BTW converting to manual is far and away the best mod i have made to my car, even over the v8 engine, it's was like driving in with one car and driving out with a different car a couple of months later.
I'm sure the fellow converts above would agree, best mod you've done guys?