Standard Harmonica Note Layouts
The following is a standard set of notes for each keyed harmonica that can assist as to which is the most appropriate choice. The keys have been arranged in the order of the Circle of 5th's to facilitate successively better selections as one gets closer to the appropriate keyed harmonica to choose for playing. This arrangement clearly shows the progression of an added sharp (#) or flat (b) for each key that is further away from the "natural" note set of the key of C. The key of Gb (vs. F#) was used to enable the flatted progression to be more obvious,
Also see the next section per available bends that expand the basic note set.
Expanded Layouts (with bends)
As shown below, all intermediate notes between each of the standard notes for each hole can also be found by either: bending the draw notes from 1 to 6 or bending the blow notes from 7 to 0. As well, the 5 hole draw and the 7 hole blow can both be slightly bent. Furthermore, a note above the highest standard note within each hole is possible (but difficult) with overblows on holes 1 to 6 or with overdraws on holes 7 to 0. And yeah — BeatTab uses 0 for hole 10.
For a complete layout of notes for every key, see Appendix A of Harmonica for Dummies by Winslow Yerxa. As mentioned before, his descriptions of positions, including avoid notes, chord issues and tonality per each position are invaluable. It even comes with some decent humor.
All the above (per the note sets of the diatonic harmonica) are included in each of the BeatTab books.
As well, some relevant assist is included for understanding of both, modes and harmonica positions.
Also check out the other 4 titles (Riffs of Ronnie Shellist, the Workbook, plus the two combo books).
Solutions for the Problematic 3'' Bend
The problematic 3'' means to play a draw bend of 2 half tones below the normal unbent 3 hole. Beginners do not often like this note and so to play the piece "correctly", one has to find a work-a-round. But TRY to learn how to play the 3'' properly so that it sounds right if possible. One can learn to do the bend right but know that it will take time. Perhaps try it on a higher pitched harmonica to make it easier to perform?
This may be the most vexing problem with the 10 hole blues harmonica as this note is so often needed. The following list gives some work-a-round methods that come to mind for helping this and similar problems:
1. Avoidance by either not playing it or at least playing it softly albeit a bit incorrect.
This only works if it is not an important emphasized note.
2. Play that portion an octave above so that the 3'' A note becomes the 6 draw A note.
This only works if the octave switch is done smoothly without interrupting the piece.
3. Substitute another note that is nearby and hope that no one will notice.
Often a repeat of the last note can be used effectively to do this.
4. Substitute a harmonizing note within the used scale using the problem note.
The 4 blow tonic note often works as it would here to help fix the problem.
5. Play two notes at the same time so giving the feel of the right note.
Similarly one can use a vibrato, trill or warble at that point to disguise the problem.
6. Switch to a different harp that can play that note easily for that portion of the piece.
This can only be done if able to do smoothly — which is not usually.
7. Switch positions (and harp so that the key does not change) so to have the right note.
This is a big move overall, but for some songs, it can simplify many issues.
8. Switch to a special tuned harp such as those with a Paddy Richter tuning.
Eg: The PowerBender by Brendon Powers has the 3 blow raised one full tone.
The above tips are also applicable for other problematic notes such as when the 5 hole draw is needed to be sharped. As said, it gets better with time. Sometimes you just have to say that the harp is not appropriate for some songs. Be realistic.