If you want to play along to the track on the Life and Limb Album then you need a Capo on 5th. 
I'm not convinced by the D in the chorus but I can't find anything better to fit.

-----------------------------------------------------------------------------
                    Martin Carthy - The Begging Song
-----------------------------------------------------------------------------

Am                   C        G                 Am
Of all the trades in England the beggin' is the best
Am                   G            C             G
For when a beggar's tired he can lay him down and rest

Chorus (after each verse):
D
And a-beggin' I will go
    Am        G      Am
And a-beggin' I will go 

Am                   C         G                     Am
I got on the train in Carlisle they kicked me out at Crewe
Am               G                 C            G
I slept on every paving-stone from there to Waterloo

Am                      C            G                Am
I got breakfast off the Embankment I got my lunch and tea
Am                  G                C                     G
And only the finest cardboard made a home that was fit for me

Am                     C                     G                  Am
We sit on the stair at Leicester Square from seven o'clock till ten
Am                         G                   C                    G
Then round the back of the Connaught House for dinner from out of a bin

Am                   C           G                Am
I can rest when I am tired and I heed no master's bell
Am                      G         C               G
A man'd be daft to be a king when beggars live so well

Am                   C                G          Am
The law came down to see us they came down three together
Am                         G             C                  G
They put out the fire they left us there Oh Lord how we did shiver

Am               C         G          Am
I am a Victorian value I'm enterprise poverty
Am                   G            C            G
Completely invisible to the state and a joy to Mrs T

Am                   C        G                 Am
Of all the trades in England the beggin' is the best
Am                   G            C             G
For when a beggar's tired he can lay him down and rest