What is the best way of doing my validation:

I have 2 asp pages: asp_page1, asp_page2

I have 3 text boxes in asp_page1 and 1 Submit button.
Once the values are entered in all three text boxes, I press the submit button and the data is submitted to asp_page2.

In asp_page2, I have 3 recordsets.

Rec1 is based on values from textbox1 and textbox2
Rec2 is based on values from textbox1 and textbox3

Rec3 is based on Rec1 and Rec2

My question is:
1) How can I show a message, when Rec1 or Rec2 is null and redirect then to asp_page1. Do I have to write a script or can I just use response.write "...."

I tried the following code:

If Rec.RecordCount = 0 or Rec1.RecordCount= 0 Then
Response.Write "....."
Response.Redirect "asp_page1.asp"
End if
This code gives me an error.

2) Can I check the value for Rec1 and Rec2 in asp_page1 and then submit it to asp_page2. How can I do these??

Thanks

Reggie