If you're on a tight budget ($30), then I would recommend the Arbans. A few months ago I sat down and figured out how much some of the different method books were, per page. In this way, the Arban book is the best value going.
Here's a list that I put together of a small selection of books. It shows how varied the prices can be, per page.
Etudes pour Trompette”
Stamp “Warm-Ups and Studies” $0.43/pg
Sachse “28 Studies” $0.37/pg
Voisin “11 Studies” $0.37/pg
Snedecor “Lyrical Etudes for Trumpet” $0.25/pg
Vacchiano “Trumpet Routines” $0.23/pg
Ricker “Technique Development in Fourths” $0.21/pg
Higgins “120 Blues Choruses” $0.19/pg
Keller “Sonny Stitt’s Greatest Solos” $0.19/pg
Weiskopf/Ricker “The Augmented Scale” $0.15/pg
Campbell “Expansions” $0.15/pg
Blatter/Zonn “Contemporary Trumpet Studies” $0.15/pg
Ricker “Pentatonic Scales for Jazz Improv.” $0.13/pg
Carley “Woody Shaw Jazz Trumpet Solos” $0.12/pg
Farmer “The Art of Art Farmer” $0.11/pg
Various “Master Works for Trumpet” $0.07/pg
Looking at this chart, I would also recommend "Master Works for Trumpet". This is a collection of four or five different etude books into one book. If you'd like publisher info and such, contact me personally.
Also, depending on where you are in your progress, I would recommend:
Getchell - First Book of Practical Studies
Potag - Preperatory Melodies for Solo Work
These are the two etude books which I use with my jr. high and early high school students. No, they are not that standard staples, but they progress in a more graduated fashion, making it easier for the students to see the benefits of their work.
Eddie "Tiger" Lewis