Sorry -I'll try again with HTML breaks. I've taken the liberty of providing a pictorial platform to explain this madness!
KEY
0 means leave the string rringing open.
X means blank the string ie. try not to strum it,or use your finger to stop it ringing.
1,2,3,4 are the numbers of you fingers, 1 being index.
This is for substituting A minor As above.
....1...2...3...4...5..<<-fret numbers
E[]---]---]---]---]-0-]
B[]---]---]---]---]-0-]
G[]---]---]---]---]-4-]
D[]---]---]---]---]-3-]
A[]---]---]---]---]-X-]
E[]---]---]---]---]-2-]

And the first chord I described: ....1...2...3...4...5..<<-fret numbers
E[]---]-2-]---]---]---]
B[]---]---]-3-]---]---]
G[]-0-]---]---]---]---]
D[]-x-]---]---]---]---]
A[]-x-]---]---]---]---]
E[]-0-]---]---]---]---]

If this goes wrong again, can someone more experienced with HTML try to fix it, PLEASE?? Cheers again, Ian