Catholic Daily Quotes

I've read a lot about the importance of SEO but I'm a bit overwhelmed by all the options out there. Can anyone recommend reputable SEO agency? I'd like to know about your experiences – did they provide tangible results? Also, what kind of services did they offer? I'm particularly interested in on-page optimization and link building. My budget isn't huge, so affordability is a factor as well. Any input would be greatly appreciated!