Message board layered architecture 2-tier or 3-tier?

Hi,

I've got a VB.Net + ASP.Net message board application which has
already been customized. There are two solutions in this application.
1. The front end aspx, aspx.vb files, User controls solution
2. A components solution which has .vb files which have the code to
call inserts, updates, deletes to the database (SQL server 2000)

Its much like the available general ASP.Net message board. Only a bit
customized. Right now a simple interaction flow from front end to
database is like this.

aspx (aspx.vb) --> usercontrols.vb --> components.vb (call for a
stored procedure in the DB) --> Database

My requirement is to understand if its possible to port this
application to a 3-tier architecture. This is to standardize all
similer applications I have to a 3-tier architecture, not because I am
looking at performance, maintinance etc.

What is the best way to do it?
I have considered couple of options.
1. Have Webservices that facilitates db interaction (What
components.vb does now)
2. Right complus components to do the same as in option 1.

I don't see a clear feasibility of the above options that I 've put
down, Is there a best way to emerge with a worthy 3-tier architecture
for this requirement? If so, what is it and how can it be
accomplished.
Any feasible idea for a 3-tier architecture is fine.

Please reply at the earliest.

Thanks much in advance,
Vin