Here, read this:
<http://www.httrack.com/html/abuse.html#WEBMASTERS>

And this:
<http://www.affiliatebeginnersguide.com/articles/block_bots.html>

But then again, that couldn't even be HTTrack, since faking a "browser"
identity is too easy..

Btw, what's your website?If you can't afford keeping it up, why you even
opened up an gallery in the first place? I hope it's not a picture gallery.
"...seeing my site let alone grab any content."
Even more fuel to question, why do you even have that site?
There's one disadvantage that most web spiders have:
They can not understand encrypted content, which require specific plugins in
browsers, e.g. Adobe Flash and Silverlight. And maybe even SSL encryption.
Learn to make content loaders like that and your webpage will be protected
against (cheap) grabbers - they'll only get the tiny encrypted Flash or
Silverlight loader. And then you only need to pray that the grabber ain't
smart enough to decrypt the loader. Even if that happens, you can think of
security measurements to put on server side. For example, setup anti-Download
Hammering - if the end user downloads too much in a row, temporary ban their
IP and give a message, that your server is weak and costs you too much to keep
up.