Walking Blues lick... played w/ shuffle, not strait time the way Clapton played it.A very long post about how to play a short lick, but I think well worth it.
 

The attached sound file has a couple measures of Bob Bozzman playing the lick the way it should sound, followed by my very poor rendition as tabbed below, first in GBd tuning, then in GDg. Bozzman's slide DVDs are great, btw!
 

Tab of lick here, followed by how to build up to it in case that helps. 

(play 1st line, then 2nd, then repeat 2nd)

d|-----------------------3-|-----------5~~~~~~~~~~~3-|

B|-------------------------|-------------------------|

G|-----------------------0-|-0--/3-0---0-0-----0---0-|  

   1 & a 2 & a 3 & a 4 & a   1 & a 2 & a 3 & a 4 & a                                    

                                   >     >         >  

d|-----------5~~~~~~~~~~~3-|-----------5~~~~~~~~~~~3-|

B|-------------------------|-------------------------|

G|-0--/3-0---0-0-----0---0-|-0--/3-0---0-0-----0---0-|

   1 & a 2 & a 3 & a 4 & a   1 & a 2 & a 3 & a 4 & a  

         >     >         >         >     >         >  
 

Closer to original feeling in GDg tuning though I can't play it as well (pls ignore my rotten vibrato on 12th fret): 
(play 1st line, then 2nd, then repeat 2nd)

g|-------------------------|----/3-0---12~~~~~~~~~~~-|

D|-----------------------3-|-0---------------------3-|

G|-----------------------3-|-0---0-0---0-0-----0---3-|

   1 & a 2 & a 3 & a 4 & a   1 & a 2 & a 3 & a 4 & a

                                   >     >           

g|----/3-0---12~~~~~~~~~~~-|----/3-0---12~~~~~~~~~~~-|

D|-0---------------------3-|-0---------------------3-|

G|-0---0-0---0-0-----0---3-|-0---0-0---0-0-----0---3-|

   1 & a 2 & a 3 & a 4 & a   1 & a 2 & a 3 & a 4 & a  

         >     >                   >     >                 


(In the 2 tabs the ">" shows where a partial chord was played in the original, helps to use as accent to get feeling. Elsewhere in this I use ">" just to indicate an accent.)
Played with shuffle feeling, so try counting the 1 & a 2 & a etc. out loud. The second note falls on downbeat of the first measure. Try
To get the feel, start by counting out the "one and a two and a..." outloud while tapping your foot on the accents shown by ">"
 

 >     >     >     >     >     >     >     >      

|1 & a 2 & a 3 & a 4 & a|1 & a 2 & a 3 & a 4 & a|

Next add an accent on the final note of each measure (tap or clap on it too):
 >     >     >     >   > >     >     >     >   >     

|1 & a 2 & a 3 & a 4 & a|1 & a 2 & a 3 & a 4 & a|
 

That will be how you come in. 
The general shuffle feeling is:
 

 >   > >   > >   > >   > >   > >   > >   > >   >

|1 & a 2 & a 3 & a 4 & a|1 & a 2 & a 3 & a 4 & a|
 

There is more accent on the second of each pair, or on the 1, 2, 3, 4, than on the "a"... dum DUM ___ dum DUM ___ dum DUM ___ dum DUM
 

Now mute the G string with your left hand and play just the rhythm played by the thumb on the G string while tapping out the 1, 2, 3, 4 with your foot (play 1st line, then 2nd, then repeat 2nd):
 

|1 & a 2 & a 3 & a 4 & a|1 & a 2 & a 3 & a 4 & a|

thumb:                 > >   > >   > >     >   > 
 

|1 & a 2 & a 3 & a 4 & a|1 & a 2 & a 3 & a 4 & a|

> >   > >   > >     >   > >   > >   > >     >   >

Next mute all the strings w/ left hand and do the same thing, but add in the index finger's rhythm:
index (play 1st line, then 2nd, then repeat 2nd):

                                   >           >  

|1 & a 2 & a 3 & a 4 & a|1 & a 2 & a 3 & a 4 & a|

                       > >   > >   > >     >   > 

           >           >           >           > 

|1 & a 2 & a 3 & a 4 & a|1 & a 2 & a 3 & a 4 & a|

 >   > >   > >     >   > >   > >   > >     >   > 

After this, refer to tab at top and add notes :)

I'll post more of this if people find it useful.