Pumpkin pie can be made from real pumpkins. The best pumpkins for pie are small and often sold specially as "pie pumpkins". Canned pumpkin is easier but making pie from real pumpkins isn't too hard. You can find tons of recipes on the internet.
As for the new tank, I'd definitely get it. How can you pass up a new tank!
However saltwater on limited funds isn't a good idea in my honest opinion. I'd set the tank up as a freshwater tank for now and then dive in to saltwater when you have more money. Saltwater tanks will suck you dry fast moneywise.
As for the cell phone company......I hate all cell phone companies and their crazy deals. That said, I currently use Verizon...mostly cause they have a cheap plan where I can call other verizon customers for free. Since my whole family uses Verizon this saves me tons of money.