Judging from the decal style the frame is a 1998 Zaskar LE. You should find a serial number on the rear dropout. First two letters are the month, letters three and four a the year. Model year 1998 started in 0997, I think.
Framesize looks like 16", measured along the seatube from centre of bottom bracket to centre top tube.
The Zaskar LE was available as a complete bike and as a frameset.
http://www.retrobike.co.uk/gallery2/d/1 ... 1998-2.pdf
The complete bike featured other cranks and other forks. I guess, this was a custom build, not unusual.
For judgement of value, we need more pics. The frame itself could fetch 150 GBP if without cracks or dents.