Have a look at the Find Method of the Range Object. There's an
example in the VBA help showing how to use it.

This could be useful!:

Private Sub cmdSearch_Click()

Set searchRng = Sheets(1).Range("A:A")

With searchRng
Set resultRng = .Find(TextBox1.Text, LookIn:=xlValues)

TextBox2.Text = TextBox2.Text & Sheets(1).Range("B" &
result.Row).Value & vbCrLf