Yes, before you do any major tomb raiding, Pangu's (pick)Axe should be a high priority. Completing the little extra areas on the first pass through is a lot easier than trying to remember where all the areas are that you had to skip, so you can go back and do them. You should get it pretty quickly, though.
But the first thing I would do after installing it is hit the consignment store to see if you can find the expensive camera there. It'll pop up there every now and again, and buying it there is cheaper than buying it in Egypt (especially if you're making a special trip for it). While the photography skill book isn't all that expensive to begin with, I'd buy it anyways if you find it there and have your sims read it. You can train photography faster by simply taking pictures, but it charges your sims every time they take a picture. With no skill level in it, most of your photos won't turn out and won't have any value if/when you sell them. However, if you get to level 3 using the book, it will only cost you $19 simoleans to get there (as opposed to several thousand by taking pictures), and when you do take pictures you'll have a better chance of getting ones that turn out. While most general pictures you'll take won't be worth a lot, some return is better than no return.