On the Votifier page, There is a files bar at the top. It will bring you to a page where you can download a version suitable to Tekkit. (I chose one from 1.2.5 since Tekkit is 1.2.5)
When you have Votifier downloaded, place it in your plugins folder. Start the server, there should be a votifier folder generated in the plugins folder.
In the config, You need to add your server host ip. You need to port-forward to 8192 which is the port votifier uses. I assume you know how to port-forward since you have a server you are advertising.
Inside that folder is a listeners folder. You download the Listeners and place them in the listeners folder. To find the listeners you want, go here: http://dev.bukkit.org/server-mods/votifier/forum/vote-listeners/Find the Listener you need. The one i use is the Listener that gives items. This also works with Tekkit IDs as well, I believe.
Add the item ids into the config and Your done.
Good Luck!!!
Post if you need details on anything else.