Spambots causing server crashes. How do I block them?
This is better solved at the Apache level.  The industry standard method for doing this is to create a honeypot directory, make it off-limits to bots in robots.txt, then logging the IP-address of those who still go there, and block it.

For an example of this, see the this page: http://www.kloth.net/internet/bottrap.php. You can set up this on shared hosting as long as you can edit .htaccess.

For a more sophisticated solution, take a look at Project Honeypot (NB: no relation to the Drupal Honeypot module).  There is already an Apache module which interfaces with Project Honeypot's IP blacklist. To install this, you ned to have access to the Apache config (usually not available on cheap shared hosting).

Edit: There already exists a Drupal module, http:BL, that uses Project Honeypot's IP blacklist, that may save you some time setting this up (thanks to @vr3690 for pointing this out).