Thank you for your interest in www.OpticsPlanet.com
. Unfortunately I have not had a chance to use that particular Tasco telescope. If you are missing the instruction manual, your best bet is to contact Tasco directly at 800-423-3537. They should be able to send you a replacement manual.
If you are just seeking some general knowledge about using a telescope, then I suggest contacting a local astronomy club. Their you would be able to get many expert tips and opinions from people who have been tinkering with them far longer then I.
I hope I've been able to help. Good Luck.