Search form using DataGridView with many Parameters(PROBLEM)

Hi!
i want to make a search form like the one in google (advance search) where you have a lot of options..
i REALLY REALLY NEED HELP... for my project in class

I have a customer database having the fields:
CustomerID
CustomerFName
CustomerLName
CustomerBalance - current balance
... and so on...

Balance has three categories:
Positive - Customer Paid ahead
Zero
Negative - Customer has debt to the business

In my search form, i have three check boxes for the positive, zero and negative..
Also, there is a combobox for the FULL NAME of the customer.. i added items to it using comboxbox.item.add(value)
Ofcourse there is a search button and lastly the datagridview for the results...

I already know how to add rows in the datagridview...
using: datagridview1.item(column,row).value = "value"

My problem is during UPDATING The datagridview! the first click of the search button would be very easy. But the next clicks would be hard because i need to remove certain rows to satisfy the (another) search parameter.. my question is.. how do I update the datagridview during runtime???
NOTE: i did not bind the datagridview to any datasource.. i added each row manually... using again : datagridview1.item(column,row).value = "Value"
It would have been very easy if i used the built-in features in Visual Studio 2005 express edition. But then, i will never learn hard coding if I depend on these..PLUS the built-in features is way confusing for me.. i can't even customize it..