, I don't use Sulfur myself and don't have Entropy installed on my main laptop, but I fired up an SL 5.5 LiveDVD ISO in VirtualBox to see how Sulfur works these days.
BTW, the SL Wiki has to be updated by users (anyone can register on the Wiki page to edit it). The small, hard-working development team are volunteers who also have day jobs, and they are busy working on the development and maintenance of the distribution. So if someone from the community who uses Sulfur does not update the Wiki article then it will not necessarily be up-to-date. Having said that, I've just had a cursory glance at the Sulfur article
in the SL Wiki and the pictures don't look that different to what I have seen now.
Anyway, I fired up Sulfur, updated the repositories, clicked on the 'Applications' tab, clicked on 'Sulfur' on the menu bar and selected 'Advanced Mode', clicked on 'Search', entered "wine" (without the quotes) in the pop-up window, hit Enter, selected "wine-1.3.18" in the list of packages, right-clicked (I had to do it twice) on the green box and selected 'Update', clicked 'OK' in the pop-up 'Please Confirm' window, clicked on 'Install', clicked on 'Commit Actions', clicked on 'Ignore' in a pop-up window telling me to install another package, clicked on 'Accept Licence' in the pop-up window for each of the packages listed, and the installation of the relevant packages is being displayed in a Progress pane as I type this.
Hopefully the above description should be enough to guide you through the process.