It is possible to organise .rpm package files, for example downloaded by hand (or wget), in a way that lets you use them as a repository for the yum tool. This way you can have your own local yum repository of .rpm files.

[root@host ~]# mkdir local-repo
[root@host ~]# mv gdisk-0.8.7-125.1.i686.rpm local-repo/
[root@host ~]# yum install createrepo
[root@host ~]# createrepo local-repo/
[root@host ~]# chmod -R o-w+r local-repo/
[root@host ~]# nano /etc/yum.repos.d/local.repo
# Put this in the file:
name=Local repository

[root@host ~]# yum update
[root@host ~]# yum install gdisk

This way you can have yum take care of dependencies when installing .rpm file packages.