1.  Installation.  
This package is not yet packaged for R at all, but lives as 3 source code
files.  To use it, put the files in some directory, and then call:

source('$PATH/eststo2.R')
source('$PATH/esttab2.R')
source('$PATH/estclear.R')

1.1  Dependencies
This depends on the 'stringr' package>

2.  Use.
To use the package, run regressions like:

results1 <- lm(y ~ x1 + x2 + x4)
results2 <- lm(y ~ x1 + x3 + x4)

Then, store each regression like:

estclear()
eststo2(results1)
eststo2(results2)

Finally, print the output like:

esttab2(filename='output.tex')

2.1 Keeping and Dropping variables
This function supports printing only a subset of the variables in an output
table.  Specify the option keep to esttab2:

keep=list('x1','x2','x3')

Similarly, you could use drop to specify the list of variable names to
drop.  If you specify both keep and drop at the same time, thta might cause
problems.

2.2 Indicators
Estout2 also supports indicator variables.  Imagine in the regressions
above we included a factor variable 't':

results1 <- lm(y ~ x1 + x2 + x4 )
results2 <- lm(y ~ x1 + x3 + x4 + t)
results1 <- lm(y ~ x1 + x2 + x4 + t)

You could then use the option: indicate=list('Time Dummies'='t.*') to
produce a row of the output table that indicates whether each model
includes the set of t factor variables.  The regular expression follows R's
regular expression syntax, and is set to match only the entire string.
Thus 't.*' will match 't1' and 't2' but not 'weight'.  It actually would
match 'television' too in this case, so be careful how you name things.

2.3 Extra Model Statistics
You can specify additional model statistics, such as the marginal effect of
your main variable, and include these at he bottom of the table near 'N'
and 'R2'.  For example, say you want the 1 standard deviation effect of x1.
You could store

effect <- sd(x1)*coef(results1)[['x1']]
eststo(results1,stats=list('Marginal Effect of x1'=effect))

And esttab would print this out as the line above R2 and N.  You have to
match the name of the stats between models if you want the stats from each
model to show up in the same row.

There are more options to make the tables look good, so look at the source
code for esttab2.  Especially in the beginning, it has some descriptions of
how the options work