tnevz wrote:...have the first half of the song be 100 bpm and the second half be 150 bpm.... I cant seem to change the tempo without changing the tempo of the whole song. Please Help!!
Thanks

sorry one part of your post says changing the song tempo, the other half says don't change the song tempo.
in arrange view the master track is at the bottom. in that track you can draw in tempo changes and set the tempo ranges. the tempo ranges affect how closely you can hit exact tempo values. IOW you might not be able to hit 100.00, but 100.1 , 101 etc. it's a bug users have complained about.
in session view name a scene 100bpm and the tempo will change to 100bpm when you launch that scene. check the manual for more tweaks you can do in a similar way, like time signature changes.