If you have autocad, it would be best to draw the profile in autocad, and then extrude them in inventor. You might also want to check out
http://www.firstcadlibrary.com There is a spur gear i-part that i think may be accurate, but i am not certian that it is. If you need information on the involute itself then check out
http://www.sdp-si.com/D190/D190cat.htm