I think they only provide the most recent episode on their site. Other than that, it's a lot of clips.
If you want to check out J.G. Quintel's earlier (more adult-themed) work, which features characters that would later be adapted into Regular Show, here; 2 in the AM PM and The Naive Man from Lollieland (skip to about 2m 56s in).
Regular Show is great stuff, though. It's a mid-90s style cartoon with late-80s/early-90s sensibilities.
If you want to check out J.G. Quintel's earlier (more adult-themed) work, which features characters that would later be adapted into Regular Show, here; 2 in the AM PM and The Naive Man from Lollieland (skip to about 2m 56s in).
Regular Show is great stuff, though. It's a mid-90s style cartoon with late-80s/early-90s sensibilities.