I'm trying to install Wordpress to my Linode so I can host my blog (currently hosted on Wordpress.com) at blog.mydomain.com. However, I'm following the Wordpress installation guide from the library and I'm not able to get to the configuration portion. Can someone help clarify the initial set up and tell me what needs to be done to get to the configuration step?

Thanks

What guide are you following exactly? What have you already tried? Did you transfer the files to Linode? Are you able to reach those files through your browser? What is your Apache/nginx config? And what OS are you using?

Gonna need more information before people can help you

I followed the "Hosting a Website" guide on the Linode Library to set everything up. I have created virtual hosts for both joshvickerson.com and blog.joshvickerson.com.

I then followed the "Manage Web Content with Wordpress" guide (here: http://library.linode.com/web-applications/cms-guides/wordpress) and set up wordpress directly in my /home/user/public/blog.joshvickerson.com folder. There are three folders in there, log, public_html, and src. I unzipped wordpress and put it in public_html. I set the permissions on the folder to 777 as the guide instructs.

The DocumentRoot for the virtual host is /home/user/public/blog.joshvickerson.com/public_html/wordpress

I updated my DNS records last night for my linode and joshvickerson.com works, but blog.joshvickerson.com does not (yes, I added the A record for blog). It has been almost 12 hours since I updated the DNS records but going to blog.joshvickerson.com results in a 404 so I'm unable to perform the initial configuration of wordpress.

Just not sure where I went wrong or what I missed.

Well, I just removed wordpress and installed it again and now everything is working... I'm not sure what happened there.

Well - you've already done it now but for future reference:
To verify whether DNS has already updated you can ping/dig/nslookup the domain to verify whether it's already using the correct IP. You could always update the hostsfile from your local PC to use the proper IP, so you can at least set stuff up and verify it's working properly.

Have fun