Photoshop is a powerhouse, it is intimidating for beginners and You really don't need it unless you have the intention on creating your own supplies.
You can still create your own supplies (basics) with photoshop elements, it lacks many features that you would want to have if you were to design. If you are just purchasing graphics and focusing on the actual scrapbooking vs creating graphics then I think photoshop elements would suit your needs much better!!
I have been digital scrapbooking/ digital scrapbook designing for 6 years now. When I am creating scrapbook layouts, I now often use photoshop elements because it gets the job done quicker.
Also, I believe they have GREAT specials occasionally for photoshop elements users to upgrade to photoshop for under 300 dollars occasionally
So, it might be worth waiting and checking into that!