So you have a nice new Warré Hive and no bees, what to do? Well the commercial option is to install a bee package. I do not like packages because I think it's hard on the bees and they seem to have a very low success rate.
A very good option is to capture a swarm. I caught one this year and it was easy and fun. If the swarm lands within reach they can be a very good source of bees. It has several advantages over buying a package. First of all with a swarm you get a lot more bees than a package. All of these bees are from the same hive unlike a package. All of the swarm bees will be keyed in on the queen already so no wait there. The swarm bees will be from your local area which means they are already acclimatized to your region. Most packages come from thousands of miles away. The bees show up tired, thirsty, and confused. Swarm bees are full of honey and ready to build a new home.
Nucs are a great option for Langstroth hives but are difficult to prepare for a Warré Hive. The frames in the Nuc are not compatible with the Warré dimensions.
I recently did a cut out for a neighbor. I was able to not only capture the bees but I was also able to keep five of their brood combs and hang them from the top bars of my Warré Hive. This is probably the best possible scenario for the bees. They get everything they need to really set up shop rapidly in a Warré Hive. The drawback to cutout's are they are quite involved and would be overwhelming for a beginner. I was fortunate to be a part of a three man team and we borrowed a bee vacuum. Luckily neither of the other guys wanted the bees so I managed to put them all in my Warré.
The new bees are rapidly building comb and seem to like their new home.