I was very excited to see what the community had to offer for this problem as I am in need of a cardboard box replacement as well. Unfortunately, it appears that www.cwcrate.com is out of business. Therefore, I continued to search for a solution. I found the following sets of plans to make wooden crates:
set 1 -- enclosed box: these look really nice, but were beyond my skill level and equipment availability, plus I really wanted a crate that would hold 24 bottles
set 2 -- plywood based crate for 24 bottles: this is exactly what I was looking for in terms of style, wood cost, size, etc... However, I do not have a table saw and ripping all that plywood would have been very difficult for me
set 3 -- same basic plans as set 2, but made from 1x2 and 1x3 furring strips (i.e. no ripping on a table saw, just cross cuts with a circular or miter saw)
I ended up going with set 3 as they were the right fit me for. My wife expressed interest in helping so I taught her how to use the power tools and she ended up cutting most of the wood and I assembled them. We bought enough wood and supplies to make 6 for around $55. Additionally, we took an idea from this picture and painted the bottom front rail of each crate with chalkboard paint to provide a place to write some information about what is in the crate.
Here is a picture of the finished almost finished product.
Eventually, we decided to add an aged look by using a process which includes black tea (to provide tannin) and steel wool dissolved in vinegar which reacts with the tannin.
Here is a picture after the aging process.