You'll not want to interactively query the transaction log - not a good idea.
It really depends what it is you're trying to trap. Using code is probably best - a job which runs every minute or so ?
You can log many events ( via alerts ) which you could get to fire off an email.
I agree with trying to avoid triggers, they can really impair your database performance.
[font="Comic Sans MS"]The GrumpyOldDBA[/font]
www.grumpyolddba.co.uk
http://sqlblogcasts.com/blogs/grumpyolddba/