Would you mind posting your xp turtle setup and the script on Pastebin? I would really like a program like yours but I have had no luck finding one.
My setup is a bit of a hack as it came from adding an xp turtle to an existing mob grinder so it probably isn't optimal for general use. I'll describe it below for those who are curious. However, a more general setup with better-commented (and probably more flexible) code is Tim the enchanter; for that see
its Reddit post and
source code.
Anyway, on the server where I play we have some tier 5 shard spawners that drop the mobs into a 1x3 hole that has 6 melee turtles (they line both sides) and I plopped the XP turtle at the end of the line closest to where the player normally waits for xp. The turtle is manually loaded with books and ejects the results into a relay above it that is connected to our tube system. The script is available at
http://pastebin.com/2QB3bzC4 and there is a rough picture of the setup below; note that the purpose of the picture was to explain the xp turtle to other players on the server already familiar with the mob grinder so it may not be all that helpful
The piston with the glass block helps block the xp orbs from reaching the player so that the turtle gets it all (our grinder requires a player to actually be there.)