hopefully this will help you
http://www.nationalrail.co.uk/planmy..._Timetable.asp

you want to use a train that has no changes as that will get confusing for you especially as you havn't had much rail travelling.
it may take some time to get to birm. i think you'll be on the train for a few hours. maybe you should take a friend along too so you are not alone.
hope that has been helpful!