Welcome to the Society!
I found great selection of orchids in bigger garden centres/flower shops, like Urban Plantlife and Johnstown garden centre. It can be a hit or miss, the best is to give them a call…(Spring and summer is the best time to look for orchids there and before Easter and Christmas, Valentine’s day and Mother’s day. The above shops are present on social media, you can see it there when fresh plants are coming in!)
Interestingly IKEA had amazing selection of orchids in late 2017/early 2018, with Phal type dendrobiums, Nobile type dendrobiums, Miltonias, Cymbidiums, I even found a sorry looking Maxillaria once… sadly these days it doesn’t have such a diverse selection.
Even Lidl had some nice orchids for Mother’s day (I got an amazing Dendrobium Berry Oda for 13e!)
Tesco had Miltonias and some intergeneric hybrids (Cambrias) for 5e at Mother’s day…
Woddies and B&Q has some other-than-phalaenopsis orchids sometimes.
For special or rare orchids the best would be online shopping… I’ll try to find time and write a little list of the websites I used and recommend…