Excel 2007 : Function where results cell equals partial "text" of reference cell??? HELP!!!

I think the best way to explain this is to attach the spreadsheet I am trying to finish:

I am trying to prepare a new sheet that totals the categories in the drop down (account codes) in H8 and subsequent cells (H9, H10 etc) and show the results in K3 (and K4, K5 etc). But I would like the results to only show the "account code numbers" (i.e. only the "6502" of the 6502 - Auto and Truck Expense-Fuels, Gas & Propane, Cost of Goods Sold).

Additionally, I would like the results cells (K3, K4, K5 etc) to consolidate and total all those that match on previous page for a respective account code "Grand Total" in L3 (etc). So if I enter 3 amounts for account code "6502" on the "Expense Report Sheet", the results cells (K3) would add all the "6502" figures on the "Expense Report Sheet" and calculate in the "Totals" cell of L3 etc.

I have attached the spreadsheet which I hope will better explain this!!! I have to get this done today and I have driven myself crazy for 5 hours now!!!


Sample Excel.xlsx