I had one traveling journal to send off today, and I couldn't make sense of the new postal rates so I walked down to the local post office to get the info from a representative of the U.S. Postal Service. I present the info here for what it's worth.
The journal I was mailing was a handmade 3.5 X 5 inch melnicki mini-masterpiece which fits comfortably inside a regular #10 envelope. I mailed it with a blank 8.5 X 11 sheet of paper folded around it (dunno why, but since that's how I received it...). It weighed more than 1 ounce, but less than 2. The addressed envelope is thicker than 1/4 inch, but less than 3/4 inch. As such, the dimensions are probably very similar to most traveling journals.
Postage = $1.00.
It was considered a "large envelope" but even though the journal occupied only a portion of the envelope, it did not require the $0.30 "nonuniform thickness" surcharge on items with more than 1/4 inch variation in thickness. I guess that technically, the enclosed journal should be no thicker than 1/4 inch to avoid the surcharge. This seems a bit subject to the "by-the-bookness" of the post office, so I guess putting $1.30 on it wouldn't hurt.
Hope this helps.
Doug
P.S. I also tried to buy 94 cent international stamps, but there is no such thing. You have to add a 4 cent stamp to the old 90 center.