These usually are available from uucp sites such as uunet or other sites as
marked; please consult the archie server to find more recent versions.
See also the comp.graphics, available from
ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/
        or
http://www.cis.ohio-state.edu/hypertext/faq/usenet/graphics/faq/faq.html 

 gnuplot	X (xplot), PostScript and a bunch of other drivers.
	ftp.x.org [and elsewhere]:R5contrib/gnuplot3.4a.tar.Z

 gl_plot	X output only [?]
	comp.sources.unix/volume18

 graph+
	ftp://yallara.cs.rmit.oz.au/pub/ [131.170.24.42]
	comp.sources.unix/volume8

 pdraw,drawplot		2D and 3D X,PS
	ftp://scam.berkeley.edu/src/local/ [128.32.138.1]
	ftp://scam.berkeley.edu/src/local/ [128.32.138.1]
	ftp://scam.berkeley.edu/src/local/ [128.32.138.1]
	uunet:~ftp/contrib/drawplot.tar.Z

 xgraph		plot, zoom. Outputs PS or HPGL.
	ftp://shambhala.berkeley.edu/pub/ [128.32.132.54]
	sun1.ruf.uni-freiburg.de:X11/contrib/xgraph-11.tar.Z [132.230.1.1]
	nisc.jvnc.net:pub/xgraph-11.tar.Z [128.121.50.7]
	comp.sources.x/volume3
	or many other sites 

 ACE/gr (formerly xvgr and xmgr) XY plotting tools	[10/95]
	ftp://ftp.teleport.com/pub/users/pturner/acegr/
	ftp://ftp.x.org/contrib/applications/

 XGobi		An interactive dynamic scatter-plotting tool from Bellcore
	lib.stat.cmu.edu: general/xgobi* [log in as statlib with your email
	as the password; or send email to statlib@lib.stat.cmu.edu containing
	the one-line message "send xgobi from general"]
	Information from: Debby Swayne, dfs@bellcore.com.

 Robot		a scientific XView-based graph plotting and data analysis tool
	ftp.astro.psu.edu:pub/astrod/robotx0.48.tar.Z [128.118.147.70]

 plotmtv	a multi-purpose 2D/3D plotter
	ftp://tanqueray.berkeley.edu/pub/
 XgPlot		Motif-based x-y graphing with a movie-loop display
	ftp.x.org:XgPlot-4.1.tar.Z

[2/91. Thanks in part to: emv@ox.com (Ed Vielmetti); geoff@Veritas.COM 
(Geoffrey Leach); Paul A. Scowen (uk1@spacsun.rice.edu); black@beno.CSS.GOV 
(Mike Black)]

See also http://www-ocean.tamu.edu/~baum/ocean_graphics.html .