To make it easier to find articles you want I created a custom search engine that only searches the 23 archaeology journals that have gone open access for open access week (Update– link removed, open access week is over so the search engine no longer works). It should make it easier to find what you are looking for. Here is the webpage(link removed)
I also created a website http://www.openaccessarchaeology.org/ it has a custom search engine that searches 270+ open access archaeology publications. It should make it easier to find open access archaeology publications.
The selection is hit or miss depending on the topic.
Apologies if the website is not up to par. I have only had a few hours to get everything up and running. Open access week is almost over.