Alas, why do you not ask a Neovictorian like myself? Let me clarify a few subjects.
First of all let me explain the base of all Victorian themed fashion. The term "Victorian Fashion" covers all sorts of clothing that have their bases in Victorianism. Two forms of Victorianism are as follows:
A Neovictorian is a person who attempts to mirror the sensibilities and formalities of Victorian times, especially those of the aristocracy.
Steampunk culture is a version of Victorianism that includes modern technology with that of the Victorian era. A Steampunk may, like a Neovictorian, instill Victorian sensibilities, but rarely will they be as high and proper as the aristocrats.
Victorian fashion influences many modern day clothing styles, but the truest forms are listed below. This will also answer your question about Steampunk and Victorian Gothic.
Steampunk fashion combines Victorian clothing with almost robotic parts and futuristic suits. Brass is a predominant factors, reckoning back to the Second Industrial Revolution.
An example:
http://media3.playstadium.dk/img/mgh/d3/billeder/cosplay/12.jpgAristocratic/ Lolita fashion, designed for males and females respectively, is most true to the real Victorian fashion. It originated in Japan and is most suiting to those who dress Neovictorian.
Classic Lolita is the most historically accurate and mature version of Lolita/ Aristocrat fashion, and focuses on the Baroque, Rocaille, and Regency styles. This form tends not to be as eccentric as some of the below fashions, but is often more intricate. It tends to use very neutral colors. (A special thank you to Catsuits for a few corrections.)
http://atashi.files.wordpress.com/2008/05/img_3276s.jpghttp://upload.wikimedia.org/wikipedia/commons/4/49/Classicloli.JPGGothic Lolita (and this should answer your questions) is similar to Classic Lolita save for the darker colors and not-so-mature style. It is very much unlike any other form of Gothic fashion from the west. The look is similar to what one would expect in a vampire movie like Dracula. Mana, a famous Japanese musician (and one of my favorites) is responsible for popularizing the style along with many other Visual Kei artists. http://home.teleport.com/~monica/livejournal/Gothic_and_lolita_bible1.jpg (that would be Mana, who is in fact a straight male)
Sweet Lolita is a more childlike style of Lolita and is heavily influenced by Rococo styles. References to Alice in Wonderland, fruits, sweets, and fairy-tales are popular themes throughout. Bright colors, bows, lace and ribbons are also a necessity.
http://img3.ak.crunchyroll.com/i/spire1/08232008/0/2/f/0/02f05a4f77e4f0_full.jpgPunk Lolita is exactly what the name says. It uses boots, safety pins, plaids, and chains in addition to Victorian dress. http://s.bebo.com/app-image/7927000463/5411656627/PROFILE/i.quizzaz.com/img/q/u/08/04/12/QUIZ-punk.jpg
The following are less common versions of Lolita:
Wa Lolita combines traditional Japanese clothing with Victorian dress.
http://nd01.blog.cz/936/475/4290cdae58_46915595_o2.jpgQi Lolita is the Chinese version of Wa Lolita.
http://www.nautiljon.com/images/galerie/mode/qi_lolita/qi_lolita_1.jpgOji, or Boystyle, is the style a young Victorian boy would wear.
http://sp8.fotolog.com/photo/8/55/8/yprh/1229955183013_f.jpgHime Lolita is akin to the clothing of European princesses.
http://media.photobucket.com/image/hime lolita/sunbeammoonpie/Lolita/hime2df.jpgGuro Lolita is the most Gothic version of the fashion. Blood, bandages, and the grotesque dominate this style.
http://sgcafe.com/attachment.php?attachmentid=117298&stc=1&d=1205501533Sailor Lolita is a combination of Japanese schoolgirl attire and Victorian dress. http://s.bebo.com/app-image/7931872762/5411656627/PROFILE/i.quizzaz.com/img/q/u/08/04/12/QUIZ-sailor.jpg
I hope this answers any future questions about the styles. Basically, a Neovictorian is to a Catholic as a Steampunk is to a Protestant; they are extremely similar but differ in minor areas. However they are still brothers.
P.S. Victorian Gothic is a kind of Literature with themes of monsters, madness, blood, and unhappy endings. Dracula, The Vampyre, Sweeny Todd, and The Count of Monte Cristo (best book ever written) are examples of this genre. It quite nearly founded what Americans know today as the Gothic subculture. How fun!