Consolidate Data From Multiple Sheets & Workbooks

I have been working on this project for some time and still haven't got anywhere with it. What I am essentially trying to do is create a master summary workbook where by you press a button to activate a chunk of VBA that will grab the same range of data from multiple workbooks but also multiple sheets in those workbooks, only problem is the number of sheets in each workbook are constantly changing so I need first find some way of accessing a closed workbooks, then I need a way of looping through a segment of code that will look into approximately 10 workbooks all with a different number of sheets and taking a fixed range of cells out of each sheet and for every workbook make a new tab and paste the information in that tab then move onto the next workbook, find the number of tabs (missing out the first 3 tabs of every workbook) and copy and paste the fixed range from each tab onto a new tab the summary workbook.
I will then have a summary workbook with a number of tabs, each one a different workbook with all the data from all the tabs in that workbook, I can then pull that information using formulas or some more VBA into a summary tab on the summary workbook, consolidating all of the information.