All surplus to requirements:
Countdown to Mathematics, Vol. 1 and 2 These are part of the OU mathematics course, and, from a quick google, are still used. ISBN 0201137305 & 0201137313
The Mathmatics Primer. K.R.Coombes et al. Probably of little use, was for Mathematica 2 IIRC, gives a breakdown of functions, and how-tos for Mathematica in Mac (classic) OS and Win 95. ISBN0521637155
Mathematics for engineers and scientists. K.Weltner et al. Pretty good, advanced book. ISBN 0859501205
Foundation Maths. A. Croft & R.Davison. Pretty good 'basic to advanced' maths book. ISBN 058223185-x
Free, but I would like a donation for the postage, or collect from here, just south of Leicester