VLOOKUP/LOOK Advice

Hi there,

I have 2 problems relating to LOOKUP.
Not sure if Excel can perform these calculations as they could get to complex.

Problem 1
Can it be possible to have excel look at data from one cell reference another cell then display the results from the cell next to it in another cell, sort of example:

Tab 1 (Never changes)
A B
Bob 1
Jon 2
Fred 3

Tab 2 (Dynamic, changes each week)
A B
Jon
Fred
Bob

So it would work as follows.
Tab2 column B will take Tab2 column A’s data check Tab1 column A and display Tab1 column B’s result.

Problem 2

Weekly league rank table that shows position movements week by week
Example.

Week1
1 Jon
2 Bob
3 Fred

Week2
1 Fred Up 2
2 Bob Not Moved
3 Jon Down 2

Can Excel calculate/show the actual movements of league positions?

Thanks in advance to any help anybody can offer, I am no way an Excel expert so sorry if I gave poor examples.

Martin.R