I'd recommend visiting the website
Try a Blade who have a great selection of blades.
When it comes to testing blades, a lot of people recommend getting 2 of each.
When it comes to DE blades made under the supervision of Gillette, the following seem to be really well appreciated on the forums
- Gillette Silver Blue
- Gillette 7 O'Clock Sharp Edge (Yellow)
- Astra Superior Platinum
- Polsilver Super Iridium
- Permasharp Super Stainless
- Sputnik
- Nacet
Blades made by other makers include
- Feather
- Personna Lab Blue
- Personna Platinum (Reds)
- Shark Super Stainless
- Voskhod
Of course there are many others the ones I have mentioned are ones that I have used or read favourable reports of, and it's about finding the blades which suit your face the most.