Hello Justint.

To manage extensions (install, uninstall, disable, enable and configure), you can go into Tools > Add-ons > Extensions. From there, you will be able to uninstall the Ask Toolbar, which is probably an extension. If it's not an extension, check the Plugins section, but I doubt it's a plugin. You may need to contact Ask if you're having troubles, since it's their software, but hopefully that won't be needed.

Also, if your keyword searches in the location bar are being redirected to ask.com, see this article: http://support.mozilla.com/en-US/kb/Searches+are+redirected+to+another+site

By the way, this ask stuff wasn't installed because of Firefox, but probably because you installed it (perhaps unknowingly) yourself, maybe as a bundle in some other software. Some software (like Winamp or uTorrent) often include this kind of software as a form of advertising for their partners, and users often forget to read the details of what they are installing. For future reference, always see if all the boxes ticked when installing software actually conform to what you want to install.