My first build along has info on sinew backing. Here's the link:
http://www.primitivearcher.com/smf/index.php/topic,9076.0.html(See Replies #39 to #43).
Everybody (except me) uses ace bandages for wrapping, not twine. Also, you can use thicker strands of sinew if the thought of spending hours applying thin strands doesn't appeal to you. I recommend staying away from bundles if you are just starting out.....they are harder to apply than individual strands, especially if you mess up and try to smooth them out or if you try to remove the bundle and re-apply it.
Sinew is not like rawhide and some people confuse the two. Sinew does not need to be soaked for long periods (like rawhide) and sinew should not be sanded too much after it is applied.
Never tried using TB as a glue for sinew backing. I've heard good things and bad. Personally, if I'm going to go through the trouble of preparing sinew, I might as well use hide glue, knox, or fish glue.