Do you need them? I'll be going into first year in September and I was wondering how many, if any, of the textbooks recommended in the handbook are needed.
Don't bother for maths. I think they're totally unnecessary and expensive for what little use you'd get out of them. The lecture notes are totally fine (obviously this only works if you go to lectures as not all of the first year maths lecturers give handouts).
I found HRW more useful than the Fundamentals of Calculus book that I bought, but neither seemed vital. They've changed the second year Physics modules since I did them and I don't know if they still give you electronic access to HRW, but I did find the paper copy useful for revision (especially since I didn't have a computer of my own at the time).
*is outdated on Physics* and I switched to Maths because I was better at it
If you do decide you want HRW or Fundamentals of Calculus then you probably don't need the latest version. Slightly earlier versions are often significantly cheaper and I don't think there's a huge difference in their content.
I've done first year physics and first and second year maths and never needed one. Even if you did decide you really wanted to look at one to get another perspective on something you can find one in the library. So I really wouldn't bother at all now and if you do decide you need one - which I doubt you will for a couple of years anyway - you can get one at the time off amazon or something.