I like the sidebar on this forum, can I get this on mine? http://www.doesntgrowontrees.co.uk/community/
In Dashboard > Appearance > Widgets admin page, wpForo creates forum specific widgets and wpForo Sidebar. You can find "wpForo Online Members", "wpForo Recent Replies" and "wpForo Search" widgets on this page. Just put those widgets to wpForo sidebar.
Also, we see forum loading problem on your website. Forum is loaded before website header. What theme you use on your site? This is a theme conflict.