So 'cloning' doesn't even come into the equation.... unless you mean they cloned your hard drive to a different hard drive, but that would be an exact replica of xp and all data, so doesn't explain why you have 'lost' SP3.
I wonder why you took pc to a shop to have xp restored. Did they restore to factory settings? (like it was when you first got it) or did they use a CD/DVD?
If it was still the original Dell XP that was on pc then you could have done that restore yourself by pressing a couple of keys.
Anyway, SP3 you can download an .iso and burn it to CD. The standalone is for all versions of XP, it's a big download 544.9 MB. ClickHere microsoft.com ignore the comment of 'Do not click download if you are updating just one computer'
ok I am doing a few things at the same time and getting my in a twist. The HD disc gave up the ghost ie I could not read to it etc so to all intents and purposes it was a dead HD. The pc actually recovered the data and transferred it to a new HD and to be honest I dont really understand what they did. I wanted all my data back quickly especially emails and that happened. I had to go away and the shop did say they could get SP3 back but it meant another trip to the shop, with the PC or they could do it remotely. I had no time. I am back now and thought of asking on here. I will try your suggestion and sorry for the wrong post.